[0001] The present invention relates to jewelry, and primarily to a magnetic clasp for jewelry.
[0002] Many pieces of jewelry are provided with a clasp for holding two ends of the jewelry
piece together. Often, when donning the jewelry piece it is necessary to hold the
two ends of the jewelry piece with one hand while manipulating and closing the clasp
with the other hand. This can require considerable dexterity, and can be difficult
for some people.
[0003] It is known to provide a clasp in which magnets assist in the closure step.
[0004] U.S. Patent No. 5,197,168 discloses a jewelry closure which comprises first and second
members held together magnetically. A mechanical safety closure is mounted pivotally
on one of the members and engages, by pivotal movement, a surface of the other member.
The mechanical safety closure can be characterized as a bale-type closure in the sense
that it wraps around the other member. Such a closure can become accidentally dislodged
from its safety catch position, for instance by engaging on a piece of clothing.
[0005] U.S. Patent No. 5,349,725 also discloses a jewelry closure in which first and second
members are magnetically held together. The closure also comprises a resilient mechanical
plate on one member which engages a shaped detent in the other member. The first and
second members are the end pieces of first and second halves of a ring which are pivotally
connected and bring the plate and shaped detent into engagement with each other, without
manipulation, when the ring is closed.
[0006] U.S. Patent No. 4,231,137 also discloses a jewelry clasp in which first and second
members are magnetically held together. One member has a projection and the other
member a groove. The projection and groove are engaged when the two members are brought
together. The magnets are mounted in opposed polarity so that they attract only when
the members are in correct orientation and repel when the members are incorrectly
oriented.
[0007] U.S. Patent No. 4,458,395 discloses a first part having a permanent magnet, and a
second part having a plug of ferro magnetic material attracted to the magnet of the
first part. A cover of non-magnetic material directs the magnetic force so that the
second part is attracted to the first part when the second part is properly aligned
with the first part.
[0008] U.S. Patent No. 5,099,659 discloses first and second parts which have attracting
magnets. One part comprises a south pole magnet and the other a north pole magnet
to provide a strong attraction. The parts have cooperating, facing indentations and
protrusions which hinder lateral separation of the parts, and at the same time provide
a slight gap between the parts to facilitate separation.
[0009] Further more attention is drawn to the document EP-A-0 462 072, which discloses a
magnetic clasp. The magnetic clasp has two mirror image halfs, each of which is attached
to the ends of a necklace. Each half has a magnetic shell and an inserted magnetic
core. The shell has a cylindrical body with a cone-shaped end. A safety latch can
be added to this clasp as a backup safety feature for expensive jewelry.
[0010] In accordance with the present invention a clasp for a piece of jewelry, as set forth
in claim 1, is provided.
[0011] Preferred embodiements of the invention are described in the dependent claims.
Summary of the Invention
[0012] The present invention relates to a clasp for a piece of jewelry. The clasp comprises
a first part and a second part. Each of said parts comprises a trailing end, a leading
end, a connection on said leading end, and a center line intersecting said ends. Said
first part comprises a receiving surface, and at least one magnet in said receiving
surface providing north and south poles on opposite sides of said first part center
line. Said second part comprises a matching surface which conforms to said first part
receiving surface when said first and second parts are engaged. The second part comprises
at least one magnet in said matching surface providing south and north poles on opposite
sides of said second part center line. When the first and second parts are engaged,
said magnets of the two parts are aligned and in an attracting relationship, the first
and second parts center lines are in the same plane, and said leading ends are oriented
in opposite directions. Locking means are provided between the first and second parts
acting along the first and second parts center lines resisting separation of the parts.
[0013] Preferably, the locking means comprises a socket in said first part receiving surface
aligned with said first part center line and a tongue in said second part matching
surface aligned with said second part center line wherein said socket and tongue resist
separation of said parts by forces acting in the direction of said parts leading ends.
Brief Description of the Drawings
[0014] Further features of the present invention will become apparent to those skilled in
the art to which the present invention relates from reading the following specification
with reference to the accompanying drawings, in which:
Fig. 1 is an enlarged perspective view of a clasp for a piece of jewelry in accordance
with the present invention; and
Fig. 2 is a section view taken along line 2-2 of Fig. 1.
Description of Preferred Embodiments
[0015] Referring to the Figures, a jewelry clasp 12 is disclosed. The clasp 12 comprises
a first part 14 and a second part 16. The first part 14 has a connection 18 which
connects to one end of a jewelry component 19. The second part 16 has a connection
20 which connects to an opposite end of the jewelry component 19.
[0016] The first part 14 is generally rectangular in configuration and comprises a longitudinal
center line 22. The first part 14 also comprises a top face 24 which is generally
planar, end faces 26 and 28, and opposed sides of which only one side 30 is visible.
Connection 18 protrudes from end face 26. End face 26 is a leading end face in the
sense that it faces in the direction in which it is pulled by jewelry component 19
attached to connection 18. End face 28 can thus be characterized as a trailing end
face.
[0017] The top face 24 comprises a raised surface 32 which is adjacent trailing end 28,
and a recessed surface 34 which is adjacent leading end 26. A transition surface 36
extends between the-raised surface 32 and the recessed surface 34. The transition
surface 36 is in a plane which is generally at right angles to the first part center
line 22. The transition surface 36 comprises a socket 38 which comprises an open end
40 facing the first part leading end 26.
[0018] The socket 38 has a generally triangular cross section, as shown by dashed line 41,
and is defined on its sides by thin webs 42 and 44.
[0019] The first part 14 also comprises a pair of magnets 48 and 50 which are embedded in
the raised surface 32 of the top face 24. The magnets 48 and 50 are adjacent the trailing
end 28 of the first part 14, and are arranged to provide a north pole on one side
of center line 22 and a south pole on the opposite side of the center line 22. The
magnets 48 and 50 are cemented or otherwise affixed into holes 52 and 54 in the first
part raised surface 32 and are substantially flush with the surface 32.
[0020] The second part 16 also has a generally rectangular configuration, which is generally
complementary to the configuration of the first part 14. The second part 16 comprises
a center line 58. The second part 16 also comprises a planar bottom face 60, a leading
end 62 to which connection 20 is attached, and an end 64 which is opposite end 62
of part 16. The part 16 also comprises side faces of which only one side face 66 is
visible. As with part 14, the end face 62 is a leading end in the sense that it is
facing in the direction in which it is pulled by jewelry component 19 attached to
connection 20. End face 64 can thus be characterized as a trailing end face.
[0021] The bottom face 60 is generally planar in a transverse direction and comprises a
raised surface 68 which is adjacent trailing end 64 and a recessed surface 70 which
is adjacent leading end 62. A transition surface 72 extends between the raised surface
68 and the recessed surface 70. The transition surface 72 is in a plane which is generally
at right angles to the second part center line 58. The transition surface 72 comprises
a tongue 74 which extends in a direction towards leading end 62. The tongue 74 has
a generally triangular configuration when viewed from the side 66 of part 16, and
is defined on its sides by triangular surfaces of which only surface 76 is visible.
As shown in Fig. 1, side 76 is slightly undercut, as is the opposite side of tongue
74, with respect to the sides (e.g., 66) of the part 16 to accommodate webs 42 and
44 of part 14.
[0022] When the two parts 14 and 16 of the clasp 12 are brought together, as shown in Fig.
2, the tongue 74 of the second part 16 seats within the socket 38 of the first part
14, providing a locking means which prevents the first and second parts 14 and 16
from being pulled apart when pulled at their leading ends 26 and 62 by connections
18 and 20, respectively. When so brought together, the tongue 74 of the second part
16 fits snugly within the socket 38 of the first part 14.
[0023] In addition to resisting longitudinal separation of the first and second parts 14
and 16, the locking means comprising the tongue 74 and the socket 38 resists lateral
or rotational movement of one part with respect to the other, such movement being
hindered in part by webs 42 and 44 of the socket 38.
[0024] The second part 16 also comprises a pair of magnets 80 and 82 which are embedded
in the recessed surface 70 of the second part 16. The magnets 80 and 82 are preferably
adjacent leading end 62 of the second part 16 and are cemented or otherwise affixed
in holes 84 and 86 in the recessed surface 70. As with part 14, the magnets 80 and
82 are generally flush with the surface 70 of the part 16, and are on opposite sides
of the center line 58 of the part 16, providing a north pole on one side of the center
line 58 and a south pole on the opposite side of the center line 58. However, the
magnets 80 and 82 are arranged in the part 16, so that when the parts 14 and 16 are
brought together, they are in an attracting relationship with respect to the magnets
48 and 50 of the first part 14, rather than in a repelling relationship. The north
pole of part 16 is aligned with and faces a south pole of part 14, and the south pole
of part 16 is aligned with and faces a north pole of part 14.
[0025] When it is desired to couple the first and second parts 14 and 16 together, it is
a simple matter to bring the two parts 14 and 16 close to one another. When brought
close to one another, the attractions of magnets 48, 50, 80 and 82 are sufficient
to snap one part into seating engagement with the other. By seating engagement it
is meant into proper alignment in which: (1) tongue 74 of part 16 seats within socket
38 of part 14; (2) raised surface 32 of part 14 seats against recessed surface 70
of part 16; (3) the center lines 22 and 58 of parts 14 and 16 are in the same plane;
and (4) magnets 80 and 82 of part 16 are aligned with the magnets 48 and 50 of part
14. In addition, the opposite sides of the parts 14 and 16, for instance sides 30
and 66, as well as ends 26, 28 and 62, 64 are all flush presenting a pleasing appearance.
[0026] The location of the magnets 48, 50, 80 and 82 prevent any alignment of the parts
14 and 16 other than the above-mentioned proper alignment. By using a pair of magnets
in each part, on opposite sides of the center lines 58 and 22, this prevents one part
16 from engaging the other part from an angle, or askew with respect to the other
part, thus facilitating coupling of the parts and introduction of the tongue 74 of
part 16 into the socket 38 of part 14. In this respect, the pairs of magnets 48, 50,
80 and 82, on opposite sides of the parts center lines 22 and 58, provide a torquing
action as well as longitudinal and lateral attraction forces which help align the
tongue 74 of part 16 with the socket 38 of part 14 and permit seating the parts snugly
one against the other. The pairs of magnets 48, 50, 80 and 82 also resist separation
of the parts 14 and 16 when one part is subjected to a torquing action with respect
to the other, as well as resisting longitudinal separation.
[0027] It will be apparent to those skilled in the art that the locking mechanism of the
present invention can have other configurations than the tongue 74 of part 16 and
the socket 38 of part 14. For instance, the tongue 74 and the socket 38 can extend
the full width of the parts 14 and 16. The side webs 42 and 44 of the socket 38 are
preferred to resist dislodgment of one part from the other from an accidental lateral
or torquing force applied to one of the parts. Also, although the tongue and socket
arrangement as shown is preferred with respect to preventing longitudinal separation
of the parts 14 and 16 by forces pulling in the parts leading directions, it is possible
to use a mechanical connection between the parts, for instance a pivotable latch on
one part engaging a catch on the other part. Such a mechanical connection can be used
with or in place of the tongue and socket arrangement shown in the Figures. With such
a mechanical connection, the principals of the present invention apply. The pivotable
latch would preferably pivot in a plane aligned with the parts center lines 22 and
58. The torquing action of the pairs of magnets 48, 50, 80 and 82, on opposite sides
of the parts center lines 22 and 58, would bring one part into alignment with the
other part so that engagement of a latch on one part with a catch on the other part
would be facilitated.
[0028] However, it has been found that the clasp of the present invention is secure without
a mechanical coupling.
[0029] To separate the parts 14 and 16, it is a simple matter to slide one part longitudinally
in a trailing direction with respect to the other part. This is done by engaging one
part with one finger and the other part with another finger and exerting trailing
direction forces on both parts. The frictional force between the parts and the fingers
is all that is necessary. Once a small separation of the parts is achieved, in a longitudinal
direction, the attracting force of the magnets 48, 50, 80 and 82 is weakened and complete
separation of the parts 14 and 16 can then be accomplished by sliding the parts sideways
with respect to each other.
[0030] The magnets 48, 50, 80 and 82 in the present invention are preferably rare earth
magnets. Good results have been obtained using magnets comprising a rare earth alloy
of neodymium, iron and boron, marketed by SGM Armtech, Inc., of New Town, Pennsylvania.
[0031] Instead of using pairs of magnets in each part, such as magnets 48 and 50 of part
14, or magnets 80 and 82 of part 16, it is possible to use pin or bar magnets having
north and south poles at opposite ends, wherein the pin or bar magnets extend in a
transverse direction laterally across the center lines 22 and 58 of the parts 14 and
16.
[0032] In the embodiment of the Figures, the magnets are very small, about 1/32nd or 1/16th
of an inch in diameter and about 1/8th or 3/8ths inch in height.
[0033] Prom the above description of the invention, those skilled in the art will perceive
other improvements, changes and modifications. Such improvements, changes and modifications
within the skill of the art are intended to be covered by the appended claims.
1. A clasp (12) for a piece of jewelry comprising:
(a) a first part (14) and a second part (16), each of said parts comprising a trailing
end (28,6), a leading end (26, 62), a connection (18, 20) on said leading end, and
a center line (22, 58) intersecting said ends;
(b) said first part (14) comprising a receiving surface (32) between said first part
leading and trailing ends, said receiving surface lying in a plane parallel to the
center line (22, 58),and at least one magnet (48, 50) in said receiving surface providing
north and south poles on opposite sides of said first part center line (22);
(c) said second part (16) comprising a matching surface (70) between said second part
leading and trailing ends, said receiving surface lying in a plane parallel to the
center line (22, 58), and conforming to said first part (14) receiving surface when
the first part and the second part are engaged and at least one magnet (80,82) in
said matching surface providing south and north poles on opposite sides of said second
part center line (58),
wherein when said first and second parts are engaged, said magnets are aligned and
in an attracting relationship, said first and second part center lines (22, 58) are
in the same plane, and said leading ends are oriented in opposite directions,
(d) locking means (74, 38) between said first and second parts acting along said first
and second parts center lines resisting separation of the parts.
2. The clasp (12) of claim 1 wherein said first part receiving surface comprises a socket
(38) aligned with said first part center line and said socket comprises an open end
(40) which faces said first part leading end, and said second part matching surface
comprises a tongue (74) aligned with said second part center line and said tongue
projects in the direction of said second part leading end.
3. The clasp (12) of claim 2 wherein said at least one magnet in each part comprises
a first magnet (48,82) on one side of the part center line providing a north pole
and a second magnet (50, 80) on the opposite of the part center line providing a south
pole.
4. The clasp (12) of claim 3 wherein said parts are molded or cast.
5. The clasp (12) of claim 3 wherein said first part socket comprises at least one end
surface resisting movement of said second part tongue in the second part leading direction
and sides resisting movement of the second part tongue in lateral directions with
respect to the first part.
1. Eine Schließe für ein Schmuckstück, die Folgendes aufweist:
(a) einen ersten Teil (14) und einen zweiten Teil (16), wobei jeder der Teile ein
Hinter- bzw. Nachlaufende (28, 6), ein Vorder- bzw. Führungsende (26, 62), eine Verbindung
(18, 20) auf dem Vorderende und eine Mittellinie (22, 58), die die Enden schneidet,
aufweist;
(b) wobei der erste Teil (14) eine Aufnahmeoberfläche (32) zwischen dem Vorder- und
Hinterenden des ersten Teils aufweist, wobei die Aufnahmeoberfläche in einer Ebene
parallel zu der Mittellinie (22, 58) liegt, und wobei zumindest ein Magnet (48, 50)
in der Aufnahmeoberfläche Nord- und Südpole auf gegenüberliegenden Seiten der Mittellinie
(22) des ersten Teils vorsieht;
(c) wobei der zweite Teil (16) eine angepasste bzw. abgestimmte Oberfläche (70) zwischen
den Vorder- und Hinterenden des zweiten Teils aufweist, wobei die Aufnahmeoberfläche
in einer Ebene parallel zu der Mittellinie (22, 58) liegt, und die mit der Aufnahmeoberfläche
des ersten Teils übereinstimmt, wenn der erste Teil und der zweite Teil in Eingriff
stehen, und wobei zumindest ein Magnet (80, 82) in der angepassten Oberfläche Südund
Nordpole vorsieht auf gegenüberliegenden Seiten der Mittellinie (58) des zweiten Teils,
wobei, wenn die ersten und zweiten Teile in Eingriff stehen, die Magnete ausgerichtet
und in einer sich anziehenden Beziehung sind, sich die Mittellinien (22, 58) des ersten
und zweiten Teils in der selben Ebene befinden und die Vorderenden in entgegengesetzte
Richtungen orientiert sind,
(d) Verschlussmittel (74, 38) zwischen den ersten und zweiten Teilen, die entlang
der Mittellinien der ersten und zweiten Teile wirken, die der Trennung der Teile widerstehen.
2. Schließe (12) nach Anspruch 1, wobei die Aufnahmefläche des ersten Teils einen Sockel
(38) aufweist, der mit der Mittellinie des ersten Teils ausgerichtet ist und wobei
der Sockel ein offenes Ende (40) aufweist, das zu dem Vorderende des ersten Teils
weist, und wobei die angepasste Oberfläche des zweiten Teils eine Zunge (74) aufweist,
die mit der Mittellinie des zweiten Teils ausgerichtet ist und wobei die Zunge in
die Richtung des Vorderendes des zweiten Teils vorragt.
3. Schließe (12) nach Anspruch 2, wobei der zumindest eine Magnet in jedem Teil auf einer
Seite der Mittellinie des Teils einen ersten Magneten (48, 82) umfasst, der einen
Nordpol vorsieht, und einen zweiten Magneten (50, 80) auf der gegenüberliegenden Seite
der Mittellinie des Teils, der einen Südpol vorsieht.
4. Schließe (12) nach Anspruch 3, wobei die Teile geformt oder gegossen sind.
5. Schließe (12) nach Anspruch 3, wobei der Sockel des ersten Teils zumindest eine Endoberfläche
besitzt, die der Bewegung der Zunge des zweiten Teils in der Führungsrichtung des
zweiten Teils und Seiten, die der Bewegung der Zunge des zweiten Teils in laterale
Richtungen in Bezug auf den ersten Teil, widerstehen.
1. Fermoir de bijou (12) comprenant :
(a) une première partie (14) et une deuxième partie (16), chacune des parties comprenant
un bord arrière (28, 64), un bord avant (26, 62), une connexion (18, 20) sur le bord
avant, et une ligne centrale (22, 58) coupant les bords ;
(b) la première partie (14) comprenant une surface de réception (32) entre ses bords
avant et arrière, la surface de réception se trouvant dans un plan parallèle à la
ligne centrale (22, 58), au moins un aimant (48, 50) dans la surface de réception
formant des pôles nord et sud sur des côtés opposés de la ligne centrale de la première
partie (22) ;
(c) la seconde partie (16) comprenant une surface d'adaptation (70) entre ses bords
avant et arrière, la surface de réception se trouvant dans un plan parallèle à la
ligne centrale (22, 58) et se conformant à la surface de réception de la première
partie (14) quand les première et seconde parties sont en contact, au moins un aimant
(80, 82) dans la surface d'adaptation formant des pôles sud et nord sur des côtés
opposés de la ligne centrale (58) de la seconde partie ;
dans lequel, quand les première et seconde parties sont en contact, les aimants sont
alignés et dans une relation d'attraction, les lignes centrales (22, 58) de la première
et de la seconde partie sont dans un même plan, et les bords avant sont orientés de
façon opposée ;
(d) un moyen de verrouillage (74, 38) entre les première et seconde parties le long
des lignes centrales des première et seconde parties, résistant à la séparation des
parties.
2. Fermoir (12) selon la revendication 1, dans lequel la surface de réception de la première
partie comprend une embase (38) alignée avec la ligne centrale de la première partie,
l'embase ayant une extrémité ouverte (40) qui fait face au bord avant de la première
partie, et dans lequel la surface d'adaptation de la seconde partie comprend une langue
(74) alignée avec la ligne centrale et la seconde partie, la langue faisant saillie
dans la direction du bord avant de la seconde partie.
3. Fermoir (12) selon la revendication 2, dans lequel ledit au moins un aimant dans chaque
partie comprend un premier aimant (48, 82) d'un côté de la ligne centrale de la partie,
formant un pôle nord, et un second aimant (50, 80) à l'opposé de la ligne centrale
de la partie formant un pôle sud.
4. Fermoir (12) selon la revendication 3, dans lequel lesdites parties sont moulées ou
coulées.
5. Fermoir (12) selon la revendication 3, dans lequel l'embase de première partie a au
moins une surface d'extrémité résistant au déplacement de la langue de la seconde
partie dans la direction avant de la seconde partie et des côtés résistant à un déplacement
latéral de la langue de la seconde partie par rapport à la première partie.